Ultrasound Blocks for the Anterior Abdominal Wall

60 | Ultrasound Blocks for the Anterior Abdominal Wall
6. Rectus Sheath Block
Savino Spadaro, Tommaso Mauri
The central portion of the anterior abdominal wall is
innervated by the anterior branches of the spinal nerve roots
from T6 to L1.
The nerves enter the rectus abdominal muscle near the
midline and lie between it and the posterior sheath (Rozen 2008).
The superior and inferior epigastric vessels run longitudinally
through the medial portion of the muscle (Figure 13.3).
The existence of myofascial intersection points on the anterior
border of the rectus muscle limits the spread of a local
anesthetic solution. The tendinous intersections of the rectus
muscle are not present at the posterior rectus sheath, which
allows local anesthetic to spread cephalic-caudally within the
ipsilateral compartment from a single injection site (Figure 6.1,
6.2).
The RSB has been used to provide surgical anesthesia as well as
postoperative analgesia for laparotomy or laparoscopic
procedures involving the abdominal midline (Finnerty 2010).
The block appears to be safe and easy to learn and perform. It
provides the anesthesiologist with another method of effective
and apparently long-lasting analgesia for common day-case
procedures. The RSB should be performed bilaterally with
relatively large volumes of local anesthetic.